Coumaphos Exposure and Incident Cancer among Male Participants in the Agricultural Health Study (AHS)

By Christensen, Carol H.; Platz, Elizabeth A. et al. | Environmental Health Perspectives, January 2010 | Go to article overview

Coumaphos Exposure and Incident Cancer among Male Participants in the Agricultural Health Study (AHS)


Christensen, Carol H., Platz, Elizabeth A., Andreotti, Gabriella, Blair, Aaron, Hoppin, Jane A., Koutros, Stella, Lynch, Charles F., Sandler, Dale P., Alavanja, Michael C. R., Environmental Health Perspectives


BACKGROUND: Coumaphos is an organophosphate livestock insecticide. Previous research in the Agricultural Health Study (AHS) cohort observed a positive association between coumaphos and prostate cancer in men with a family history of prostate cancer.

OBJECTIVES: This study was performed to determine the association between coumaphos and other major cancer sites and to explore the consistency of the association with prostate cancer early (1993-1999) and later (2000-2005) in AHS follow-up.

METHODS: This study included 47,822 male licensed pesticide applicators. Incident cases were ascertained by linkage to state cancer registries, and exposure data were collected by enrollment questionnaire. Poisson regression was used to estimate rate ratio (RR) and 95% confidence interval (CI) of cancer for coumaphos exposure controlling for potentially confounding variables.

RESULTS: Approximately 8% of applicators reported use of coumaphos; 8.5% reported a family history of prostate cancer. Cumulative exposure to coumaphos was not associated with cancer risk overall or with any major cancer site including prostate. In men with a family history of prostate cancer, we observed a positive association between ever use of coumaphos and prostate cancer in both early (RR = 2.07; 95% CI, 1.19-3.62, p-interaction = 0.005) and later (RR = 1.46; 95% CI, 0.89-2.40; p-interaction = 0.11) periods of follow-up. Across all years, this association was statistically significant (RR = 1.65; 95% CI, 1.13-2.38; p-interaction = 0.004).

CONCLUSION: Coumaphos was not associated with any cancer evaluated here. In men with a family history of disease, there was evidence of an association between coumaphos and prostate cancer, possibly due to genetic susceptibility; however, other explanations, including chance, are plausible.

KEY WORDS: agriculture, cancer, coumaphos, insecticide, livestock, neoplasms, occupational exposure, organophosphate, pesticide, prostate. Environ Health Perspect 118:92-96 (2010). doi:10.1289/ehp.0800446 available via http://dx.doi.org/[Online 11 September 2009]

**********

Coumaphos [O,O-diethyl O-(3-chloro-4-methyl-2 oxo-2H-l-benzopyran-7-yl) phosphorothioate], an organophosphate (OP) insecticide first registered in 1958, is used to control pests on beef cattle, dairy cows, goats, horses, sheep, and swine [U.S. Environmental Protection Agency (EPA) 1996]. Approximately 83% of the total chemical usage is on beef and dairy cattle. From 1990 to 1999, approximately 71,000 pounds of coumaphos were used on 6 million livestock annually (Smearman 2000). Coumaphos is applied primarily as a liquid (animal immersed in an insecticide-containing dip) but is also applied through a hand-held sprayer or dust formulation (U.S. EPA 1996). In addition to direct exposure to coumaphos among agricultural workers, family members of agricultural workers may be secondarily exposed in the home through contact with contaminated clothing or equipment (Arcury et al. 2007). The general population may be exposed through consumption of coumaphos-treated food products--for example, milk from coumaphos-treated dairy cattle (Cardeal Zde and Dias Paes 2006). However, commercial pesticide products containing the active ingredient coumaphos cannot be purchased by the general public.

In vitro studies indicate coumaphos is not mutagenic using either Salmonella typhimu-rium or Escherichia coli assays with and without metabolic activation (U.S. EPA 1996). There was no evidence of carcinogenicity or increased tumor formation in two 2-year feeding studies in different strains of rat (dose range: 1-25 ppm and 10 and 20 ppm, respectively), in one strain of mouse (dose range: 10 and 20 ppm), or in one 1-year feeding study in beagle dogs (dose range: 1-90 ppm) (U.S. EPA 1996). Dosing regimens in the four animal feeding studies were adequate to detect cancer based on range-finding studies. In 1994, the U.S. EPA classified coumaphos as a group E carcinogen: no evidence of carcinogenicity based on studies of at least two animal species.

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

Coumaphos Exposure and Incident Cancer among Male Participants in the Agricultural Health Study (AHS)
Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.